diff --git a/Apps/NxDomainOverrideApp/App.cs b/Apps/NxDomainOverrideApp/App.cs
new file mode 100644
index 00000000..34999b73
--- /dev/null
+++ b/Apps/NxDomainOverrideApp/App.cs
@@ -0,0 +1,252 @@
+/*
+Technitium DNS Server
+Copyright (C) 2024  Shreyas Zare (shreyas@technitium.com)
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+using DnsServerCore.ApplicationCommon;
+using System;
+using System.Collections.Generic;
+using System.Net;
+using System.Net.Sockets;
+using System.Text.Json;
+using System.Threading.Tasks;
+using TechnitiumLibrary;
+using TechnitiumLibrary.Net.Dns;
+using TechnitiumLibrary.Net.Dns.ResourceRecords;
+
+namespace NxDomainOverride
+{
+    public sealed class App : IDnsApplication, IDnsPostProcessor
+    {
+        #region variables
+
+        bool _enableOverride;
+        uint _defaultTtl;
+        Dictionary<string, string[]> _domainSetMap;
+        Dictionary<string, Set> _sets;
+
+        #endregion
+
+        #region IDisposable
+
+        public void Dispose()
+        {
+            //do nothing
+        }
+
+        #endregion
+
+        #region private
+
+        private static string GetParentZone(string domain)
+        {
+            int i = domain.IndexOf('.');
+            if (i > -1)
+                return domain.Substring(i + 1);
+
+            //dont return root zone
+            return null;
+        }
+
+        private bool TryGetMappedSets(string domain, out string[] setNames)
+        {
+            domain = domain.ToLowerInvariant();
+
+            string parent;
+
+            do
+            {
+                if (_domainSetMap.TryGetValue(domain, out setNames))
+                    return true;
+
+                parent = GetParentZone(domain);
+                if (parent is null)
+                {
+                    if (_domainSetMap.TryGetValue("*", out setNames))
+                        return true;
+
+                    break;
+                }
+
+                domain = "*." + parent;
+
+                if (_domainSetMap.TryGetValue(domain, out setNames))
+                    return true;
+
+                domain = parent;
+            }
+            while (true);
+
+            return false;
+        }
+
+        #endregion
+
+        #region public
+
+        public Task InitializeAsync(IDnsServer dnsServer, string config)
+        {
+            using JsonDocument jsonDocument = JsonDocument.Parse(config);
+            JsonElement jsonConfig = jsonDocument.RootElement;
+
+            _enableOverride = jsonConfig.GetPropertyValue("enableOverride", true);
+            _defaultTtl = jsonConfig.GetPropertyValue("defaultTtl", 300u);
+
+            _domainSetMap = jsonConfig.ReadObjectAsMap("domainSetMap", delegate (string domain, JsonElement jsonSets)
+            {
+                string[] sets = jsonSets.GetArray();
+
+                return new Tuple<string, string[]>(domain.ToLowerInvariant(), sets);
+            });
+
+            _sets = jsonConfig.ReadArrayAsMap("sets", delegate (JsonElement jsonSet)
+            {
+                Set set = new Set(jsonSet);
+
+                return new Tuple<string, Set>(set.Name, set);
+            });
+
+            return Task.CompletedTask;
+        }
+
+        public Task<DnsDatagram> PostProcessAsync(DnsDatagram request, IPEndPoint remoteEP, DnsTransportProtocol protocol, DnsDatagram response)
+        {
+            if (!_enableOverride)
+                return Task.FromResult(response);
+
+            if (response.DnssecOk)
+                return Task.FromResult(response);
+
+            if (response.OPCODE != DnsOpcode.StandardQuery)
+                return Task.FromResult(response);
+
+            if (response.RCODE != DnsResponseCode.NxDomain)
+                return Task.FromResult(response);
+
+            DnsQuestionRecord question = request.Question[0];
+
+            switch (question.Type)
+            {
+                case DnsResourceRecordType.A:
+                case DnsResourceRecordType.AAAA:
+                    break;
+
+                default:
+                    //NO DATA response
+                    return Task.FromResult(new DnsDatagram(response.Identifier, true, response.OPCODE, response.AuthoritativeAnswer, response.Truncation, response.RecursionDesired, response.RecursionAvailable, response.AuthenticData, response.CheckingDisabled, DnsResponseCode.NoError, response.Question, response.Answer, response.Authority, response.Additional) { Tag = response.Tag });
+            }
+
+            string nxDomain = question.Name;
+
+            foreach (DnsResourceRecord record in response.Answer)
+            {
+                if (record.Type == DnsResourceRecordType.CNAME)
+                    nxDomain = (record.RDATA as DnsCNAMERecordData).Domain;
+            }
+
+            if (!TryGetMappedSets(nxDomain, out string[] setNames))
+                return Task.FromResult(response);
+
+            List<DnsResourceRecord> newAnswer = new List<DnsResourceRecord>();
+            newAnswer.AddRange(response.Answer);
+
+            foreach (string setName in setNames)
+            {
+                if (_sets.TryGetValue(setName, out Set set))
+                {
+                    switch (question.Type)
+                    {
+                        case DnsResourceRecordType.A:
+                            foreach (DnsResourceRecordData rdata in set.RecordDataAddresses)
+                            {
+                                if (rdata is DnsARecordData)
+                                    newAnswer.Add(new DnsResourceRecord(nxDomain, DnsResourceRecordType.A, DnsClass.IN, _defaultTtl, rdata));
+                            }
+                            break;
+
+                        case DnsResourceRecordType.AAAA:
+                            foreach (DnsResourceRecordData rdata in set.RecordDataAddresses)
+                            {
+                                if (rdata is DnsAAAARecordData)
+                                    newAnswer.Add(new DnsResourceRecord(nxDomain, DnsResourceRecordType.AAAA, DnsClass.IN, _defaultTtl, rdata));
+                            }
+                            break;
+
+                        default:
+                            throw new InvalidOperationException();
+                    }
+                }
+            }
+
+            return Task.FromResult(new DnsDatagram(response.Identifier, true, response.OPCODE, response.AuthoritativeAnswer, response.Truncation, response.RecursionDesired, response.RecursionAvailable, response.AuthenticData, response.CheckingDisabled, DnsResponseCode.NoError, response.Question, newAnswer) { Tag = response.Tag });
+        }
+
+        #endregion
+
+        #region properties
+
+        public string Description
+        { get { return "Overrides NX Domain response with custom A/AAAA record response for configured domain names."; } }
+
+        #endregion
+
+        class Set
+        {
+            #region variables
+
+            readonly string _name;
+            readonly DnsResourceRecordData[] _rdataAddresses;
+
+            #endregion
+
+            #region constructor
+
+            public Set(JsonElement jsonSet)
+            {
+                _name = jsonSet.GetProperty("name").GetString();
+                _rdataAddresses = jsonSet.ReadArray<DnsResourceRecordData>("addresses", delegate (string item)
+                {
+                    IPAddress address = IPAddress.Parse(item);
+
+                    switch (address.AddressFamily)
+                    {
+                        case AddressFamily.InterNetwork:
+                            return new DnsARecordData(address);
+
+                        case AddressFamily.InterNetworkV6:
+                            return new DnsAAAARecordData(address);
+
+                        default:
+                            throw new NotSupportedException("Address family not supported: " + address.AddressFamily.ToString());
+                    }
+                });
+            }
+
+            #endregion
+
+            #region properties
+
+            public string Name
+            { get { return _name; } }
+
+            public DnsResourceRecordData[] RecordDataAddresses
+            { get { return _rdataAddresses; } }
+
+            #endregion
+        }
+    }
+}
diff --git a/Apps/NxDomainOverrideApp/dnsApp.config b/Apps/NxDomainOverrideApp/dnsApp.config
new file mode 100644
index 00000000..b719056d
--- /dev/null
+++ b/Apps/NxDomainOverrideApp/dnsApp.config
@@ -0,0 +1,23 @@
+{
+  "enableOverride": true,
+  "defaultTtl": 300,
+  "domainSetMap": {
+    "*": ["set1"],
+    "example.com": ["set1", "set2"]
+  },
+  "sets": [
+    {
+      "name": "set1",
+      "addresses": [
+        "192.168.10.1"
+      ]
+    },
+    {
+      "name": "set2",
+      "addresses": [
+        "1.2.3.4",
+        "5.6.7.8"
+      ]
+    }
+  ]
+}